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Lanthanide ion contained metal–organic frameworks (MOFs) have garnered significant attention in the fields of solid‐state lighting and chemical sensing due to their porous structure and distinctive optical properties. However, they also present challenges because of the limited photoluminescence (PL) intensity resulting from the parity‐forbidden f–f transitions of lanthanide ions. Herein, the study reports a new heterometallic MOFs Ln3Li2L4 (Li‐Ln‐MOF, Ln = Y, Eu, Tb and Dy, L = deprotonated 1,3,5‐tris(4‐carboxyphenyl)benzene) with a Brunauer‐Emmett‐Teller (BET) surface area of 774.1 m2/g. The porous crystal structure of Li‐Ln‐MOF is characterized by three kinds of channels interpenetrating with each other. By employing ligand alternation and lanthanide ion alloying strategies, Li‐Y1‐xEux‐MOF1 crystal isostructural with Li‐Ln‐MOF is synthesized by using 2,4,6‐tris(4‐carboxyphenyl)‐1,3,5‐triazine (H3TATB) as ligand. The Li‐Y0.7Eu0.3‐MOF1 crystal excels in the comprehensive performance with a BET surface area of 858.8 m2 g−1 and a near‐unity PL quantum yield. The time density functional theory and natural transition orbitals calculations unravel that the outstanding optical properties Li‐Y0.7Eu0.3‐MOF1 originates from the charge transfer between TATB3− and Eu3+. Benefiting from the excellent comprehensive performance of Li‐Y1‐xEux‐MOF1, the study reveals their potentials as single‐composition white‐light emission and fluorescent sensing probe for the detection of nitrobenzene. [ABSTRACT FROM AUTHOR]

Improving polarizability is an important strategy for designing high‐performance mid‐infrared (mid‐IR) nonlinear optical (NLO) materials. The substitution of equivalent or aliovalent atoms can manipulate the polarizability by adjusting the symmetry of the polyhedron. Herein, the Li+ and Cd2+ are introduced into the Cu3PS4 as the equivalent and aliovalent dopants for the Cu site. As a result, Li+ can significantly improve the bandgap (Eg) of LixCu3−xPS4 from 2.38 to 2.88 eV, leading to a higher laser‐induced damage threshold (LIDT) of 4.9 times than AgGaS2 (AGS) with a comparable second harmonic generation (SHG) response of AGS (26−45 µm). Interestingly, Cd2+ can improve the SHG response and enlarge the Eg simultaneously. As a result, Cd0.4Cu2.2PS4 has a large SHG response of 10 × AGS at 2050 nm (26−45 µm) and a LIDT of 2.6 × AGS. Theoretical calculations reveal that lattice vacancies induced by Cd2+ significantly boost polarizability compared to LixCu3−xPS4 with no vacancy, leading to a strong NLO response. [ABSTRACT FROM AUTHOR]

As a class of emerging photoluminescent materials, hybrid halide crystals have drawn research attention for their potential application in the fields of light‐emitting, security, and waveguide. Nevertheless, hybrid halide crystals containing antimony with long‐term stability and tunable light emission are still increasingly in demand. In this work, serial new hybrid halide crystals (BZA)2ZnCl4·2H2O:xSb3+ (x = 0–0.2, x represents the reaction ratio) and (BZA)2SbCl5 are synthesized (BZA = 2,4‐diamino‐6‐phenyl‐1,3,5‐triazine). In (BZA)2ZnCl4·2H2O:xSb3+ crystals, Sb3+ cations replace partial Zn2+ cations to form [SbCl4]− tetrahedron. Red light emission caused by the substitution of Sb3+ for Zn2+ enhances as the doping rate increases, resulting in the tunable emission from light blue to pink and finally to dark red. There are two kinds of Sb3+ in (BZA)2SbCl5 crystal. Sb(1) has a sixfold coordination with Cl to form a [Sb(1)Cl5]∞ 1D zigzag chain. Sb(2) atom adopts a fivefold coordination with Cl and is separated from each other by BZA+ cations. (BZA)2SbCl5 crystal shows bright orange‐yellow light emission with a photoluminescence quantum yield of 45%. Moreover, the organic–inorganic hybrid metal halide crystals containing antimony have excellent long‐term stability, with phase and luminescence keeping nearly unchanged after more than six months in ambient air. [ABSTRACT FROM AUTHOR]